PO.IM01.03 · 免疫学
Claudin 6疫苗在同基因小鼠结肠癌模型中有效抑制肿瘤生长
Claudin 6 vaccines effectively inhibit tumor growth in a syngeneic mouse colon cancer model
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
人Claudin 6（CLDN6）是Claudin蛋白家族的成员，该家族在紧密连接的结构和功能中发挥关键作用。在人体中，CLDN6主要表达于干细胞和胚胎组织，在睾丸、胰腺和胎盘中检测到的mRNA极少。CLDN6在多种癌症中表达升高，提示CLDN6是靶向免疫治疗的理想肿瘤相关抗原，尽管其在癌症中的确切作用仍有待明确。在此，我们生成了由多个人CLDN6 B细胞和T细胞表位组成（CLDN6-B+T）或仅含T细胞表位（CLDN6-T）的重组蛋白，这些表位是基于计算预测的B/T细胞表位序列选定的，并与白喉毒素跨膜结构域（DTT）融合作为免疫增强剂。这两种疫苗的免疫原性和抗肿瘤活性在小鼠模型中进行了评估。在野生型和HLA*02:01人源化小鼠中，CLDN6-B+T和CLDN6-T联合佐剂CpG诱导了稳健的细胞免疫反应，这通过使用连续6周每周接种疫苗的小鼠脾细胞进行的IFNgamma ELISpot检测来评估。在使用CLDN6人源化MC38结肠癌细胞系（MC38-CLDN6(K)）的同基因小鼠肿瘤模型中，与仅接受佐剂的对照小鼠（每组n=8）相比，两种疫苗均显著抑制了在第6剂疫苗后一天接种的肿瘤细胞的生长。在本研究中，接种CLDN6-B+T的小鼠中有7/8只、接种CLDN6-T的小鼠中有8/8只在终点时无肿瘤。使用独立衍生的CLDN6人源化MC38细胞系MC38-hCLDN6(C)的重复研究显示，与佐剂对照（每组n=10）相比，CLDN6-B+T和CLDN6-T疫苗分别使肿瘤生长抑制72.6%和73.2%。在一项治疗性研究中，MC38-hCLDN6(C)细胞在每周接种疫苗（共5次）前一天皮下接种，与仅接受佐剂的小鼠（n=10）相比，接种CLDN6-T（n=11）和CLDN6-B+T（n=12）的小鼠肿瘤生长分别被抑制67.0%和81.0%。总的来说，我们的发现证明CLDN6靶向疫苗显著抑制了小鼠中CLDN6阳性肿瘤的生长。这些结果支持将CLDN6靶向疫苗作为治疗人类CLDN6阳性癌症的一种有前景的治疗策略，其潜力有待在即将开展的研究中进一步验证。
查看英文原文 English abstract
Human Claudin 6 (CLDN6) is a member of the Claudin family of proteins, which plays a crucial role in the structure and function of tight junctions. In humans, CLDN6 is primarily expressed in stem cells and embryonic tissues, with minimal mRNA detected in testis, pancreas, and placenta. Elevated expression of CLDN6 has been found in several types of cancers, suggesting that CLDN6 is an ideal tumor-associated antigen for targeted immunotherapy, albeit its precise role in cancer remains to be defined. Here, we generated recombinant proteins consisting of multiple human CLDN6 B- and T-cell epitopes (CLDN6-B+T) or T-cell epitopes only (CLDN6-T), which were selected based on computationally predicted B/T-cell epitope sequences and fused with the transmembrane domain of diphtheria toxin (DTT) as an immune enhancer. The immunogenicity and anti-tumor activity of these two vaccines were evaluated in mouse models. In both wildtype and HLA*02:01-humanized mice, CLDN6-B+T and CLDN6-T with adjuvant CpG induced robust cellular immune response as assessed by IFNgamma ELISpot assay using splenocytes collected from mice vaccinated weekly for 6 weeks. In a syngeneic mouse tumor model using CLDN6-humanized MC38 colon cancer cell line (MC38-CLDN6(K)), both vaccines significantly suppressed the growth of tumor cells inoculated one day after the 6th vaccine dose, compared to control mice that received adjuvant only (n=8 in each group). In this study, 7/8 mice vaccinated with CLDN6-B+T and 8/8 mice vaccinated with CLDN6-T were tumor-free at the endpoint. A replicate study using an independently-derived CLDN6-humanized MC38 cell line, MC38-hCLDN6(C), demonstrated 72.6% and 73.2% tumor growth inhibition by CLDN6-B+T and CLDN6-T vaccines, respectively, compared to adjuvant controls(n=10 in each group). In a therapeutic study in which MC38-hCLDN6(C) cells were inoculated subcutaneously one day before weekly vaccination for 5 times, tumor growth was inhibited by 67.0% and 81.0% in mice vaccinated with CLDN6-T (n=11) and CLDN6-B+T (n=12), respectively, compared to mice that received adjuvant only (n=10). Collectively, our findings demonstrate that CLDN6-targeted vaccines significantly suppressed the growth of CLDN6-positive tumors in mice. These results support CLDN6-targeted vaccines as a promising therapeutic strategy for CLDN6-positive cancers in humans, with their potential to be further validated in upcoming studies.
利益披露 Disclosure
N. Wang, None..
L. Chow, None..
M. Toh, None..
H. Wang, None.